My opinion; a good yard manager would find out how this happened and take responsibility. Determining how this happened could uncover some other mistakes.

Partly for the problem you are going through I try and do most of the work on my boat myself. However there will always be something I can't do and I have to rely on someone else. In those cases I try to oversee everything they do by being on the boat and observing. However that being said there are some yards that don't want you around in which case the yards reputation would be a big factor in releasing work to them.

The service manager did find and open a clean out plate on top of the Stainless Steel water tank. He and I both agreed that to start with the fuel would have to be sucked off the top of it, not drained. Followed by a regimen of flushing and detergent. And, maybe alcohol?

I had indeed run the fresh water system before my discovery, but only very little and the hope is that the fuel did not get into the piping as the water supply to the fresh water pump feeds off of the bottom of the tank.

I will send out a water sample at the end of the process for eval.

I had run the tanks down to about 1/4 full each before coming to the yard as the tanks had to be drained to install valving on the sight tubes. This was done by pumping from one tank to the other with a portable fuel pump connected to to the sump valves on the tanks. I watched some of that.

And I gave no instructions to fill the tanks. I was going to do it this weekend. And...the fuel tanks are not filled. And she went directly from the travelift to a berth with no stop at the fuel dock. I was there.

Our fuel fills are located port and stbd in recesses and clearly labeled. Our water fill, clearly labeled, both on the fill cap and on a black plastic plaque, is in a recess in the cockpit.

I'm mad but resigned. No use hopping up and down and screaming.

I'll just have to ride herd on the yard to do what it takes to fix it properly.

Maybe we'll solve the mystery of how it happened on Monday when the yard crew comes to work. But maybe not as it might endanger someone's job to fess up.

[[QUOTE]
Greetings,
Mr. dw. NOT good! Sounds like you're going to be getting a total potable water plumbing rebuild from the yard. I wouldn't trust a fuel contaminated water system at all. I don't care how many times it's washed and rinsed ANY plastic in the system will have absorbed who knows what which will leach into your "fresh" water system for years. Shame to be without a boat but more of a shame to be without the ability to use it. Ditto on the lab testing.

__________________
RTF ]

RTF is correct

There's nothing you can do to take that taste out. You'll need to force them to change the complete water system for a new one. Even if they could clean it all, your brain would always bring that taste back to your mouth.
Sorry for the bad news!

suggestion: Yard is not going to like replacing the tank and will likely argue to clean the tank. Call a tank manufacturer and ask them if diesel can be cleaned from the inside of a tank so that the water is potable and the taste is gone. If they say no ask them to put it in an email to show to the yard. If that doesn't work try to get some other authority to state that diesel cannot be cleaned out of a plastic tank and the water potable.

I can't imagine why a worker would put diesel ($$$) in any boat without being told, especially on the hard. Never seen a fuel hose laying around that could get confused with water unless it was tied up at the fuel dock.
At some point the yard is going to say "done", like it or not.

Anytime any of us boaters spill a couple of drops of diesel overboard, all the local, state and federal authorities have a fit, and no one is drinking directly out of the river.

Maybe you should just contact them for their opinion on whether a water system contaminated with diesel can be adaquately cleaned to be usable again in their opinion - they All Always love to give us their Opinions and Directives....

OK,OK-
made that mistake on our boat a few years ago. STBD walkway has two fuel and one water fill and I was adding diesel. After 5 gallons the handle clicked as though full. Luckily the tank (100 gallon SS under aft cabin bunk) was almost full. I was obviously upset as I knew the problems associated with the diesel contamination in the water heater, tanks, lines, etc. I turned the valve off to the tank and pondered it overnight and came up with the same approach originally mentioned by kulas44. I pulled the inspection cover on top, used my handy/ dandy wet and dry vac and drew off all of the diesel floating on the top. I seem to remember using the white absorbent pads for the remaining few "drops" still floating. After draining the water in the tank to about the last 1" using the water system pump straight into a sink, I vacuumed the remaining water and put in buckets just in case I missed something. I can't remember my exact approach on the fill hose cleaning, but I suspect I probably used Simple Green sprayed over and over in the hose followed by copious amounts of fresh water.Followed this by vacuuming tank and wiping out again. When I was satisfied all was clean, I filled the water tank back up, confirmed no visible diesel or odor, and it has been a non issue ever since. As long as diesel was never introduced into the system past that tank I think you will be fine.

This is not the first time this has ever happend, no need to over react. And no, they will not replace the entire system. The reason for the alcohol flush is to remove the detergent. If not done you will taste detergent for a long time, even longer than you would taste diesel if you just flushed the system with water. Personally, I like the taste of diesel better than detergent, at least the diesel can be rinsed out of your mouth with a good stiff drink. Detergent cannot.

Like posts 34 & 35. Thanks guys. Especially the tip on rinsing one's mouth out with a good stiff drink. Perhaps I should insist that the yard, at its' expense, fill up the tank for the final flush with 120 gallons of a good bourbon of my choice. Then I'd have to make the agonizing choice of do I really want to flush it all out at once, or sip by sip.

Man, you are taking the high road on the this one. Good on you, your attitude is commendable. But, it needs to be made right. In my State there is a department that offers free water testing kits for home owners. Pick up the kit and test, they will anaylize for a fee. Let 'em know what you're up against and they can isolate especially for fuel contamination. Good luck. There is always a remedy.

On a more light hearted note...There was a time when I was supervising the gas dock at a marina and a customer came in to dock with an old restored woody. After tying him off we went to fuel him up and he said, "NO. Nobody touches my boat. My son will do it." Okay, no problem. Well, the fuel fill was right in front of the empty flag pole opening. Yep, his son went for the flag pole hole and it was one big fascinating fountain of fuel covering the cockpit! Shit does happen.
Good luck with your outcome. It will work out.

If it's a plastic tank, there will never be a complete cleanse. The plastic has a small amount of porosity in the surface. The smell will last forever. New tank. You may be able to get by with the RRRR squared. but it will return upon sitting for a while.

Hopefully (as mentioned) no one used the potable system, and the stuff didnt circulate in the pump, water heater and pipes. In all likelihood since fuel floats, and the tank suction is on the bottom, none has gotten as far as the potable system. RRRR is the solution. BUT, depending upon the age of the tank, and the time to clean it, it may be more cost effective to replace the tank. If its' a SS tank, then completely emptying it, and hot water will clean it to edible standards. Re reading your OP, it is a SS tank. filling it with water will displace the fuel out of the tank. They can suck off the top all they want. until they overflow the tank, and force the fuel out the top, it won't really get all the fuel out. Then empty the water and soap, rinse, and hot water rinse. Hot water (or steam) is how we clean fuel tanks on barges for change of cargo, or shipyard.